Friction and wear properties of particle-reinforced iron-based composites under continuous high temperature braking

The particle-reinforced iron-based composites were prepared by powder metallurgy in this paper, and the friction and wear properties of the iron-based composites were investigated under the continuous high-temperature braking conditions. The friction coefficient, torque, stability coefficient, and wear rate of the iron-based composites were studied by the scanning electron microscope, energy dispersive spectroscope, and thermocouple temperature measurement, and the corresponding wear mechanism was analyzed. The results show that, as the increase of joining time, the temperature of friction pairs increases significantly, and the formation of friction films with the multilayer structure on the surface can effectively reduce the adhesion tendency and the furrow effect. Accordingly, the average friction coefficient and average torque show the trend as rising first and then falling, and the stability coefficient decreases. The joining of friction pairs in the early stage is dominated by adhesive wear and abrasive wear with the relatively high wear rate; while in the later stage of joining, the friction films serve as the protective film, and the fatigue wear between the layers and edges of the friction films is mostly found in the process with the lower wear rate.